Mercurial (Hg) with TortoiseHg might be a good option. You could even create a pre-configured PG version, to make it even easier for novices. Along with a guide on the basics, I think that could end up working quite well.
Hg also has the benefit, compared to Git, of being strictly cross-platform.
I think Mercurial (and Git) is ridiculously complex for a non-technical user (say, my mother, who has helped with translation projects online, using Word + email). TortoiseHg is great as a GUI version, but it doesn't effectively reduce the complexity - you still need to understand the basic concepts of a DVCS to use it.
In graph, they'd be like:
|--|------------------------------|-------------------------------|
git hg wiki actually usable
by non-techies
Completely agree, but with this limited use case it should be easy to provide a tool to abstract away the complexity and give them easy access to the very few features they need.
